Stability Characteristics of Misaligned Journal Bearing

A parametric study is performed to illustrate the effects of angular misalignment on the nondimensional
load capacity, nondimensional stiffness and damping coefficients, threshold speed and critical whirl
ratio of journal bearing. Film thickness and pressure are perturbed with respect to the revised coordinate
system derived from the combination of journal radial displacements and angular rotations. The dynamic
Reynolds equation is solved using Finite Difference Method using Lund and Thomsen’s[1] infinitesimal
perturbation method. Linearized eight stiffness and damping coefficients are derived as force coefficients
from combined linear and angular perturbations, while moment coefficients are neglected in the analysis.
The journal bearing with angular misalignment in either vertical or horizontal directions operates at
higher threshold speed and hence has higher stability than aligned bearing.